The present invention relates to a paper feeding device for use with an electrophotographic copier, facsimile transceiver, laser beam printer or similar image forming equipment.
A paper feeding device for the above application is often implemented with a paper cassette removably mounted on the side of image forming equipment and loaded with a stack of paper sheets. Alternatively, a plurality of paper storing sections in the form of paper cassettes or trays may be arranged in multiple stages within image forming equipment and a base on which the equipment is mounted, as disclosed in Japanese Patent Publication No. 1374/1989, for example. The problem with the removable paper cassette scheme is that a substantial part of the cassette protrudes sideways from the equipment, increasing the overall size of the equipment and, therefore, the space for installation. The multi-stage paper storing sections are successful in reducing the overall size of the equipment since they do not protrude from the equipment. However, this kind of scheme requires the operator to pull out the paper cassette, tray or similar paper storing section every time the size of paper sheets stacked therein has to be changed. To save time and labor, therefore, such paper feeding device uses as great a number of paper storing sections as possible, but this undesirably increases the overall height of the equipment. It has been customary to limit the height of the individual paper storing sections and thereby the number of paper sheets to be stacked therein for the purpose of reducing the overall height of the equipment. In such a configuration, however, the paper storing section accommodating paper sheets of a commonly used size are apt to run out of the paper sheets in a short time, and, therefore, has to be supplied with paper sheets very often. In addition, since all the paper storing sections such as cassettes or trays have the same configuration, a substantial wasteful space is left in each of the sections which are loaded with paper sheets of relatively small sizes on the side opposite to the paper feed side.